Senate votes to limit military detention

11/30/12 12:03 AM EST

The U.S. Senate voted Thursday night to prohibit the use of law-of-war powers to detain U.S. citizens or legal residents captured on U.S. soil.

The measure, proposed by Sen. Dianne Feinstein (D-Calif.) as an amendment to the National Defense Authorization Act, passed 67-29. A total of 20 Republicans joined with 46 Democrats and one independent to back Feinstein's proposal. Most Republicans voted against the measure, as did Democratic Sens. Joe Manchin of West Virginia, Ben Nelson of Nebraska, Mark Pryor of Arkansas and independent Sen. Joe Lieberman of Connecticut.

The key language in Feinstein's amendment reads: "An authorization to use military force, a declaration of war, or any similar authority shall not authorize the detention without charge or trial of a citizen or lawful permanent resident of the United States apprehended in the United States, unless an Act of Congress expressly authorizes such detention."

Feinstein said the legislation would guarantee that Americans and permanent residents of the U.S. who are detained in the country are tried in the civilian justice system. A variety of civil rights and civil liberties groups said they supported Feinstein's goal, but opposed her amendment because it appeared to authorize military detention for some foreigners even when captured on U.S. soil.

Since the September 11, 2001 attacks, the Supreme Court has not ruled on when, if at all, the government has the authority to use law-of-war powers inside the United States. In 1942, the Supreme Court approved the use of military commissions to convict eight men—including one American citizen—detained as German spies on Long Island. However, some experts including Feinstein say the case did not bless military detention apart from a war crimes case. (The current law governing military commissions bars their use to charge U.S. citizens.)

In a separate vote earlier in the evening, senators approved, 54-41, another amendment that seeks to make permanent a ban on moving Guantanamo Bay prisoners to the United States. Such transfers are banned under the current year's defense authorization bill and various appropriations measures. The language offered by Sen. Kelly Ayotte (R-N.H.) would put such a ban in place indefinitely.

Earlier Thursday, the White House threatened a veto of the defense bill prior to the latest amendments being offered. Aides to President Barack Obama have also indicated that he objects to measures like Ayotte's, but since he has previously signed bills containing similar legislation it is difficult to see why the president would refuse to do so this time around.